Does Laemmli buffer depolymerize actin/microtubules? - (Mar/21/2010 )

Hello,

If I lyse my cells directly with 1x Laemmli buffer, does that cause cytoskeleton to depolymerize? I ask because I've noticed that when I lyse with RIPA buffer and spin down max, I always see a pellet, but when I use Laemmli buffer and spin down max, I do not see a pellet. Where does all the cell "junk" go?